Monodomain liquid crystal elastomers (LCEs) are prepared using liquid crystal block copolymers (LCBCPs) comprised of a nematic liquid crystal (NLC) main‐chain polyester linked to cross‐linkable polymethacrylate (PMA) at both ends. LCBCPs at a PMA weight fraction of ≈30% are doped with a tetra‐thiol compound, stretched in one direction, and then illuminated by UV light, yielding LCBCPs that formed microlamellae consisting of alternate stacking crosslinked PMA blocks and NLC polyester blocks. The LC director lay along the stretching direction (SD). Raising the temperature to the NLC isotropization temperature, the crosslinked LCBCP strips fixed at one end contracted reversibly by a factor of 1.2–1.4 along the SD, deforming the microlamellae. The strips fixed at both ends increased the tensile stress to ≈200 kPa while maintaining the microlamellae undeformed. Regardless of strip fixation at one or both ends, the NLC decreased the orientational order. The contraction amounts and the tensile stress of strips are well associated with decreased NLC orientational order.
{"title":"Monodomain Liquid Crystal Elastomers Composed of Main‐Chain Type Nematic Polyester Bonded to Rubbery Segments at Both Ends","authors":"Ryoji Suzuki, Yuki Ikeda, Suzune Ito, Mikihiro Hayashi, Naruki Kurokawa, Masatoshi Tokita","doi":"10.1002/macp.202400214","DOIUrl":"https://doi.org/10.1002/macp.202400214","url":null,"abstract":"Monodomain liquid crystal elastomers (LCEs) are prepared using liquid crystal block copolymers (LCBCPs) comprised of a nematic liquid crystal (NLC) main‐chain polyester linked to cross‐linkable polymethacrylate (PMA) at both ends. LCBCPs at a PMA weight fraction of ≈30% are doped with a tetra‐thiol compound, stretched in one direction, and then illuminated by UV light, yielding LCBCPs that formed microlamellae consisting of alternate stacking crosslinked PMA blocks and NLC polyester blocks. The LC director lay along the stretching direction (SD). Raising the temperature to the NLC isotropization temperature, the crosslinked LCBCP strips fixed at one end contracted reversibly by a factor of 1.2–1.4 along the SD, deforming the microlamellae. The strips fixed at both ends increased the tensile stress to ≈200 kPa while maintaining the microlamellae undeformed. Regardless of strip fixation at one or both ends, the NLC decreased the orientational order. The contraction amounts and the tensile stress of strips are well associated with decreased NLC orientational order.","PeriodicalId":18054,"journal":{"name":"Macromolecular Chemistry and Physics","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141928909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Front Cover: The free volume within materials is crucial for gas adsorption and diffusion. Size and distribution of internal fractional free volume significantly impact barrier performance. This study innovatively combines experiments and theoretical calculations to corroborate that methylene group growth in aliphatic units leads to decreased crystallinity, elevated free volume fraction, enhanced segment mobility, ultimately diminishing barrier properties. More details can be found in article 2400051 by Zhiyong Wei and co-workers.
{"title":"Barrier Properties of Biodegradable Aliphatic–Aromatic Copolyesters (PBXT Series)","authors":"Lizheng Wang, Zhu Tu, Jiaming Liang, Zhiyong Wei","doi":"10.1002/macp.202470030","DOIUrl":"10.1002/macp.202470030","url":null,"abstract":"<p><b>Front Cover</b>: The free volume within materials is crucial for gas adsorption and diffusion. Size and distribution of internal fractional free volume significantly impact barrier performance. This study innovatively combines experiments and theoretical calculations to corroborate that methylene group growth in aliphatic units leads to decreased crystallinity, elevated free volume fraction, enhanced segment mobility, ultimately diminishing barrier properties. More details can be found in article 2400051 by Zhiyong Wei and co-workers.\u0000\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure></p>","PeriodicalId":18054,"journal":{"name":"Macromolecular Chemistry and Physics","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/macp.202470030","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141934488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rafał Bielas, Sarinj Fattah, Łukasz Mielańczyk, German Pozdeev, Sally‐Ann Cryan, Andreas Heise
Chemically cross‐linked hydrogels are synthesized from a set of protected L‐lysine and L‐glutamic acid containing homo and copolypetides. Cross‐linking of the linear copolypeptides is achieved through the incorporation of L‐tryptophan and its reaction with hexamethylene bis(triazolinodione). Upon deprotection, hydrogels with oppositely charged polypeptides of different L‐lysine and L‐glutamic acid composition form pH‐dependent polyion complexes through electrostatic interaction. The obtained networks show distinct pH‐dependent differences in their water swelling and rheological properties. Hydrogels at pH 4 display higher strengths compared to pH 8 and their rheological properties scale with L‐lysine/L‐glutamic acid ratio. At pH 8 results suggests that ionic interactions and presumably secondary structure effects have a significant impact on the hydrogel properties. This is further evident from the influence of the copolypetide structures, random versus block copolypeptides, used in the cross‐linked hydrogel. None of the hydrogel shows any significant cytotoxicity against skin cell lines.
{"title":"Compositional Influence of Cross‐linked Polyion Hydrogels from Poly(L‐Lysine) and Poly(L‐Glutamic Acid) on Their Properties for Potential Skin Applications","authors":"Rafał Bielas, Sarinj Fattah, Łukasz Mielańczyk, German Pozdeev, Sally‐Ann Cryan, Andreas Heise","doi":"10.1002/macp.202400201","DOIUrl":"https://doi.org/10.1002/macp.202400201","url":null,"abstract":"Chemically cross‐linked hydrogels are synthesized from a set of protected L‐lysine and L‐glutamic acid containing homo and copolypetides. Cross‐linking of the linear copolypeptides is achieved through the incorporation of L‐tryptophan and its reaction with hexamethylene bis(triazolinodione). Upon deprotection, hydrogels with oppositely charged polypeptides of different L‐lysine and L‐glutamic acid composition form pH‐dependent polyion complexes through electrostatic interaction. The obtained networks show distinct pH‐dependent differences in their water swelling and rheological properties. Hydrogels at pH 4 display higher strengths compared to pH 8 and their rheological properties scale with L‐lysine/L‐glutamic acid ratio. At pH 8 results suggests that ionic interactions and presumably secondary structure effects have a significant impact on the hydrogel properties. This is further evident from the influence of the copolypetide structures, random versus block copolypeptides, used in the cross‐linked hydrogel. None of the hydrogel shows any significant cytotoxicity against skin cell lines.","PeriodicalId":18054,"journal":{"name":"Macromolecular Chemistry and Physics","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141934484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Patinya Karoh, Maiko K. Okajima, Tatsuo Kaneko, Thapakorn Tree‐Udom
Composite xerogel films with structural orientation, controlled swelling degree, and drug‐release ability are prepared using biocompatible megamolecular liquid crystalline polysaccharide (sacran) secreted by a cyanobacterium Aphanothece sacrum. The sacran xerogel films (Sac‐XFs) are formed by drying sacran aqueous solution including vitamin C (L‐ascorbic acid, AA) and trehalose under various conditions. In X‐ray diffraction and differential scanning calorimetry of Sac‐XFs, diffractions or melting points of either AA or trehalose are not detected, indicating no crystal formation. Additionally, the stability of entrapped AA in Sac‐XFs is evaluated through changes in film color and percentage loss, to indicate that AA stability is enhanced by entrapment in Sac‐XFs in the presence of trehalose. Scanning electron microscopy of Sac‐XFs reveals the morphological orientation, and number of striped lines along the longitudinal axis of film edges on side views while no visible textures in top views. When Sac‐XFs are immersed in water, anisotropic swelling is observed, and anisotropy decreases with an increase in the drying temperature of the films. AA is released preferentially from the hydrogel sheet edges, indicating the direction‐controlled release. Thus, the trehalose/sacran composite xerogels offer an alternative platform for preserving and controlled‐releasing sensitive substances for fields of foods, pharmaceutics, and cosmetics.
利用一种蓝藻（Aphanothece sacrum）分泌的具有生物相容性的大分子液晶多糖（sacran），制备了具有结构取向、可控溶胀度和药物释放能力的复合异凝胶薄膜。在不同条件下，通过干燥含有维生素 C（左旋抗坏血酸，AA）和曲哈糖的囊兰水溶液，形成囊兰异凝胶薄膜（Sac-XFs）。在对 Sac-XFs 进行 X 射线衍射和差示扫描量热时，没有检测到 AA 或曲哈琉糖的衍射或熔点，这表明没有晶体形成。此外，还通过薄膜颜色和损失百分比的变化评估了 Sac-XFs 中夹带 AA 的稳定性，结果表明，在有曲卤糖存在的情况下，AA 被夹带在 Sac-XFs 中会增强其稳定性。Sac-XFs 的扫描电子显微镜显示了其形态取向，侧视图显示了沿薄膜边缘纵轴的条纹线数量，而俯视图则看不到纹理。当将 Sac-XFs 浸入水中时，可观察到各向异性的膨胀，各向异性随着薄膜干燥温度的升高而减小。AA 优先从水凝胶片边缘释放，这表明其释放是受方向控制的。因此，三卤糖/撒克然复合异构凝胶为食品、制药和化妆品领域提供了另一种保存和控制释放敏感物质的平台。
{"title":"Efficient Stabilization and Directional‐Controlled Release of Vitamin C in Disaccharide/Megasaccharide Composite Xerogels","authors":"Patinya Karoh, Maiko K. Okajima, Tatsuo Kaneko, Thapakorn Tree‐Udom","doi":"10.1002/macp.202400125","DOIUrl":"https://doi.org/10.1002/macp.202400125","url":null,"abstract":"Composite xerogel films with structural orientation, controlled swelling degree, and drug‐release ability are prepared using biocompatible megamolecular liquid crystalline polysaccharide (sacran) secreted by a cyanobacterium <jats:italic>Aphanothece sacrum</jats:italic>. The sacran xerogel films (Sac‐XFs) are formed by drying sacran aqueous solution including vitamin C (L‐ascorbic acid, AA) and trehalose under various conditions. In X‐ray diffraction and differential scanning calorimetry of Sac‐XFs, diffractions or melting points of either AA or trehalose are not detected, indicating no crystal formation. Additionally, the stability of entrapped AA in Sac‐XFs is evaluated through changes in film color and percentage loss, to indicate that AA stability is enhanced by entrapment in Sac‐XFs in the presence of trehalose. Scanning electron microscopy of Sac‐XFs reveals the morphological orientation, and number of striped lines along the longitudinal axis of film edges on side views while no visible textures in top views. When Sac‐XFs are immersed in water, anisotropic swelling is observed, and anisotropy decreases with an increase in the drying temperature of the films. AA is released preferentially from the hydrogel sheet edges, indicating the direction‐controlled release. Thus, the trehalose/sacran composite xerogels offer an alternative platform for preserving and controlled‐releasing sensitive substances for fields of foods, pharmaceutics, and cosmetics.","PeriodicalId":18054,"journal":{"name":"Macromolecular Chemistry and Physics","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141968927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cenk Kurtulus, Mustafa Ciftci, Mehmet Atilla Tasdelen
In the current study, a novel radical‐induced cationic frontal polymerization (RICFP) concept capable of rapid curing at room temperature via visible light irradiation is represented. Initially, the optimal formulation, which can be most effectively cured with visible light irradiation, is determined based on thickness, hardness, curing speed, and mechanical properties using FT‐IR, DSC, TGA, and flexural test methods. Subsequently, the viability of the method is illustrated by fabricating glass fiber‐reinforced composites through the hand lay‐up technique, employing the optimized formulation and glass fibers in various forms (chopped strand mat and biaxial). Mechanical properties of the obtained composites, including bending, tensile, and shear tests, are carried out according to relevant international standards and compared with reference composites thermally cured with amine‐based hardener by conventional method.
{"title":"A Novel Route to Glass Fiber‐Reinforced Epoxy Matrix Composites: Visible Light Activated Radical Induced Cationic Frontal Polymerization","authors":"Cenk Kurtulus, Mustafa Ciftci, Mehmet Atilla Tasdelen","doi":"10.1002/macp.202400080","DOIUrl":"https://doi.org/10.1002/macp.202400080","url":null,"abstract":"In the current study, a novel radical‐induced cationic frontal polymerization (RICFP) concept capable of rapid curing at room temperature via visible light irradiation is represented. Initially, the optimal formulation, which can be most effectively cured with visible light irradiation, is determined based on thickness, hardness, curing speed, and mechanical properties using FT‐IR, DSC, TGA, and flexural test methods. Subsequently, the viability of the method is illustrated by fabricating glass fiber‐reinforced composites through the hand lay‐up technique, employing the optimized formulation and glass fibers in various forms (chopped strand mat and biaxial). Mechanical properties of the obtained composites, including bending, tensile, and shear tests, are carried out according to relevant international standards and compared with reference composites thermally cured with amine‐based hardener by conventional method.","PeriodicalId":18054,"journal":{"name":"Macromolecular Chemistry and Physics","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141872666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Diabetic foot ulcer has become a heavy burden to the healthcare system with the high and growing incidence of diabetes. Persistent bacterial infections in diabetic wounds can lead to chronic inflammation and delayed wound healing. To address these challenges, a dual‐crosslinked antibacterial hydrogel loaded with anti‐inflammatory compound asiaticoside is developed in this study. The hydrogel demonstrated suitable gelation properties, good biocompatibility, and exceptional antibacterial activity. In a diabetic foot ulcer model on rats, the asiaticoside‐loaded hydrogel can alleviate inflammation, promote angiogenesis, and accelerate wound healing. Therefore, this asiaticoside‐loaded antibacterial hydrogel shows considerable potential for diabetic wound healing.
{"title":"Dual‐Crosslinked Antibacterial Hydrogel for Treatment of Diabetic Foot Ulcers","authors":"Zheng Zou, Zhen Zhang, Yang Gao, Huixian Yuan, Ting Guo, Chaoliang He, Xuesi Chen","doi":"10.1002/macp.202400163","DOIUrl":"https://doi.org/10.1002/macp.202400163","url":null,"abstract":"Diabetic foot ulcer has become a heavy burden to the healthcare system with the high and growing incidence of diabetes. Persistent bacterial infections in diabetic wounds can lead to chronic inflammation and delayed wound healing. To address these challenges, a dual‐crosslinked antibacterial hydrogel loaded with anti‐inflammatory compound asiaticoside is developed in this study. The hydrogel demonstrated suitable gelation properties, good biocompatibility, and exceptional antibacterial activity. In a diabetic foot ulcer model on rats, the asiaticoside‐loaded hydrogel can alleviate inflammation, promote angiogenesis, and accelerate wound healing. Therefore, this asiaticoside‐loaded antibacterial hydrogel shows considerable potential for diabetic wound healing.","PeriodicalId":18054,"journal":{"name":"Macromolecular Chemistry and Physics","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141872661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This research presents the optical limiting properties of a novel axially linked D‐A type compound, LaPc‐C60(OH)n, where lanthanide phthalocyanine serves as the donor and fullerenol as the acceptor. The incorporation of fullerenol expands the π‐conjugated system, decreases the aggregation of the phthalocyanine, and significantly increases the solubility of the compound. The establishment of this D‐A system promotes intramolecular electron transfer, effectively improving both the non‐linear optical (NLO) response and optical limiting properties. In addition, homogeneous poly(methyl methacrylate) (PMMA) composite films (LaPc‐C60(OH)n/PMMA) are prepared using a simple solution casting method. Compared to fullerenol or lanthanum phthalocyanine individually, LaPc‐C60(OH)n exhibited a superior NLO response both in solution and in the solid composite film. In particular, LaPc‐C60(OH)n/PMMA demonstrated an increase in the non‐linear absorption coefficient (2050 cm GW−1) and a larger third‐order magnetization (1.84 × 10−8 esu). In addition to exhibiting an excellent NLO response at 532 nm, LaPc‐C60(OH)n also shows significant NLO enhancement at 1064 nm, extending the limiting range into the near‐infrared region. This behavior is attributed to different nonlinear absorption mechanisms and the synergistic effect that arise from the photo‐induced electron transfer process between the fullerenol and LaPc.
{"title":"Preparation and Third‐Order Nonlinear Optical Properties of Novel Axial Fullerenol‐Substituted Phthalocyanines","authors":"Rui Xu, Haonan Xu, Min Zhu, Wei Li, Yunhe Zhang","doi":"10.1002/macp.202400186","DOIUrl":"https://doi.org/10.1002/macp.202400186","url":null,"abstract":"This research presents the optical limiting properties of a novel axially linked D‐A type compound, LaPc‐C60(OH)n, where lanthanide phthalocyanine serves as the donor and fullerenol as the acceptor. The incorporation of fullerenol expands the π‐conjugated system, decreases the aggregation of the phthalocyanine, and significantly increases the solubility of the compound. The establishment of this D‐A system promotes intramolecular electron transfer, effectively improving both the non‐linear optical (NLO) response and optical limiting properties. In addition, homogeneous poly(methyl methacrylate) (PMMA) composite films (LaPc‐C60(OH)n/PMMA) are prepared using a simple solution casting method. Compared to fullerenol or lanthanum phthalocyanine individually, LaPc‐C60(OH)n exhibited a superior NLO response both in solution and in the solid composite film. In particular, LaPc‐C60(OH)n/PMMA demonstrated an increase in the non‐linear absorption coefficient (2050 cm GW<jats:sup>−1</jats:sup>) and a larger third‐order magnetization (1.84 × 10<jats:sup>−8</jats:sup> esu). In addition to exhibiting an excellent NLO response at 532 nm, LaPc‐C60(OH)n also shows significant NLO enhancement at 1064 nm, extending the limiting range into the near‐infrared region. This behavior is attributed to different nonlinear absorption mechanisms and the synergistic effect that arise from the photo‐induced electron transfer process between the fullerenol and LaPc.","PeriodicalId":18054,"journal":{"name":"Macromolecular Chemistry and Physics","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141872670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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